渗铌层的组织与性能研究

The study of the Microstructure and Properties of Niobium Case-hardening Layer

采用45~#、T10A等四种钢经固体渗铌处理,通过金相、X射线衍射分析和硬度测量对其渗层动力学影响因素、金相形貌和物相、硬度等进行了研究。结果表明:高碳钢能获得较高的硬度,若碳量较低需进行碳铌共渗或先渗碳再渗铌才能获得较高的硬度。渗铌层是由NbC-Nb_2C和NbFe组成的比合物层。推荐的渗铌可用1050℃×4～6h,催渗剂用CaCl_2,渗层厚度可达0.03～0.05mm。铝热法渗铌的铝量在氧化铌量的15～20%为宜。

In this paper, the niobium case-hardening of 45, T1OA, 4Cr5MoV1Si, and W9Mo3Cr4V2 steels using solid niobiumizing had been studied. The factor of effect on the dynamics, microstructure and properties of the niobiumizing layer investigated through metalloscopy, X-ray diffraction and microhardness testing. The results show that the high carbon steels can get high hardening layer earsily, and it is necessary for low-carbon steels to use carbon-niobimnizing or the first carbonization followed by niobiumizing. The niobiumizing layer is composed of NbC-Nb_2C and FeNb. And the optimizing process parameters were evaluated. Aluminium amounts of niobimizing by solid-alumi-nothermy was 15～20% that of niobium oxide.